Controller for motor-driven traveling devices



Jan. 30, 1945. E. w. SEEGER 2,353,333

CONTROLLER FOR MOTOR DRIVEN TRAVELING DEVICES Filed June 17, 1943 3 Sheets-Sheet l L @Mxl' w I Z5 1 25 as F- ,4

Jan. 30, 1945. w, SEEGER 2,368,383

CONTROLLER FOR MOTOR DRIVEN TRAVELING DEVICES Filed June 17, 1943 3 Sheets-Sheet 2 A 6 k a /a Q a Jan. 30, 1945. O E. w. SEEGER CONTROLLER FOR MOTOR DRIVEN TRAVELING DEVICES Filed June 17, 1943 3 Sheets-Sheet 3 1 a Q gf 64 66 68 L I I 96 L Fir. 52* 95 94 FiP 95 9a 91 Patented Jan. 30, 1945 CONTROLLER FOR MOTOR-DRIVEN TRAVELING DEVICES Edwin W. Seeger, Wauwatosa, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a corporation of Delaware Application June 1'7, 1943, Serial N0. 491,095

Claims. (Cl. 187-29) The present invention relates to control for electric motor driven traveling devices and is particularly applicable to and advantageous for control of elevators.

Where it is desired to control elevators from various landings as by push button switches with registration of a plurality of calls for automatic stopping of the elevator car at the landings for which calls are set up, it has been found necessary heretofore to provide costly and complicated mean and circuits to effect the desired automatic stopping. Cost and complication are especially great where the stopping depends not only upon entry of the elevator car into the landing zones registered, but also upon the direction of travel.

of the elevator car into each zone.

The present invention has among its objects to provide suitable control for elevators and other traveling devices affording the aforediscussed and other features with simplification of the control apparatus and of the control circuits.

Another object is to provide a control system of the aforementioned nature which requires a minimum of electromagnetic switching apparatus.

Another object is to provide a control system in which energy is stored up incident to actuation of a push button switch for registering a call at a desired landing and to provide for discharging "the stored energy upon entry of the car into a given zone of travel to efiect stoppage of the car. Another object is to provide a control system in which energy is stored up incident to actuation of a push button switch for registering a call at a desired landing and. to provide for discharging said stored energy subject to control by position and direction of travel of the car to effect stoppage of the car. 7

Another object is to provide a control system of the aforementioned type which permits an operator in the car to by-pass at will any floor even though a call for said floor may have been registered previously. 7

Another objectv is to provide a control system of the aforementioned type including means for slowing down the elevator 'car prior to stoppage thereof in response to a registered call.

Another object is to provide a system of the aforementioned type for the joint control of a plurality of elevator cars or other conveyors which jointly serve the same landings.

Other objects and advantage will hereinafter appear.

The accompanying drawings are illustrative of several embodimentsfof the invention.

In the drawings, Figure l is a diagram of a controller for a direct current single speed elevator incorporating the invention.

Fig. 2 is a modification of th system shown in Fig. 1, wherein the operator in the car can pass by a floor even though a push button on said floor has previously been depressed.

Fig. 3 is another modification of the system shown in Fig. 1, providing for slow down of the elevator prior to stoppage.

Fig. 4 is a modification of the system illustrated in Fig. 1, providing means to reduce the capacity of certain condensers shown in Fig. 1.

Fig. 5 is a modification of Fig. 3 providing for an alternate slowdown of the car prior to stoppage, while Fig. 6 is a system similar to Fig. 1, but adapted to control a plurality of cars from a common set of landing push buttons.

Referring to Fig. 1, the same comprises a direct current elevator motor I, having an armature 2, and a shunt field winding 3. The motor is connected to the elevator hoist mechanism in any suitable manner (not shown), and may be supplied with energy from the direct current lines L L which also supply the energy for operating the various control instrumentalities. The shunt field winding 3 is energized upon energization of the lines L L One terminal of the energizing winding 4 of an electromagnetic brake for the motor is con- 'nected to one terminal of the motor armature 2. Energization of the motor armatur 2 and of the energizing winding 4 is controlled by a pair of electromagnetic reversing switches 5 and 6. The forward switch 5 is provided with an energizing Winding 5 normally open main contacts ii and 5 and normally open auxiliary contacts 5 ,'5 and 5 The reverse switch 6 is provided with an energizing winding B normally open main contacts 6 and 6 and normally open auxiliary contacts 6 6 and (i The system further includes a relay 1 having .two energizing windings l and 1, respectively, and normally closed contacts 1.

The system as shown is for an elevator serving four floors. Mounted at the landing of the second, third and fourth floors are push button switches 8'; 8, and 8 respectively, for stopping the elevator when running in the upward direction toward the respective floor. There are also installed at'the first, second and third floors, similar push button switches 9; 9 and 9, respectively, for controlling the downward movement of the elevator. Push button switches 10*, lo l0 and III, are installed in the car of the elevator to cause the elevator to stop at the first,

second, third or fourth floor, respectively, when ing the car switch 25.

respectively by a bridging contact II provided with a nut engaging the screw of shaft I I. Similarly the floor selector I2 is provided with contacts I2, I2 and I2", which are connected to the segment I2", by a bridging contact I2, upon the car being adjacent to the first, second or third floor, respectively. The floor selector I3 is provided with stationary contacts I3and I3 con- -nectable to the segment I3 by a bridging contact I3 reciprocated by engagement with the screw shaft I3, when the elevator car is adjacent to the second and third floors, respectively.

Each push button switch has a. terminal connected to line L and the push button switches IIJ III", 9, 9*, 8, 9, 8 and 8 are connected to condensers I4, I5, I6, II, I8, I8, and 2|, respectively. The other terminals of said condensers are jointly connected to the line L The push button switch Ill is connected in parallel with push button switch 9, and the push button switch IIZI is connected in parallel with the push button switch 8.

A double throw car switch is mounted in the elevator car. The car switch is provided with a contact lever 25 normally biased to a neutral position and operable in opposite directions from said neutral position to selectively engage stationary contacts 25 and 25, for controlling the movement of the car in the upward or downward direction, respectively. The system further includes a normally closed hatchway limit switch 22, which is opened when the car reaches the highest position in the hatchway, and a similar limit switch 23 which is opened when the car reaches the lowermost position in the hatchway. There are also provided the usual safety devices such as overloads, door interlocks, and the like, which are indicated in the diagram in a general way by the switches 24.

The system shown with the car positioned 0pposite the first landing, operates in the following manner: If the operator wishes to start the car in an upward direction he moves the car switch 25 counter-clockwise, thereby establishing a circuit from line L contact lever 25 contact 25', through coil 5, limit switch 22, contact 1, safety devices 24 to line L This energizes the forward switch 5, thereby closing contacts 5*, 5, 5, 5

and 5 and a circuit is established from line L over contact 5, through the armature 2, over contacts 5 to line L while current also passes from contacts 5", through the Winding 4 of the electromagnetic brake through contacts 5 and 5 to L The brake is thus lifted and the motor rotates in the direction to raise the car.

Closure of auxiliary contact 5 establishes a maintaining circuit from line L over contacts 5, through the coil 5, over the circuit already traced to line L. Thus the switch 5 remains energized when the operator releases the handle of the car switch 25, and thereby opens the circuit in the latter. The car thus ascends; until'it reaches the fourth floor, in which position the limit switch 22 is opened, thereby deenengizing the switch 5 and causing disconnection of the motor armature and deenergization of the brake 4 whereupon the motor stops.

While the car is ascending from the first to the fourth floor, the limit switches I I, I2 and I3. progressively connect their stationary contacts to their respective segments in the manner already described. If the operator wishes the car to stop on the third floor, however, he pushes the push button Ifl either before or after operat- This completes a circuit from line L over push button I0, through the condenser I5 to line L and the condenser is charged. Upon reaching the third floor the limit switch I3 completes a circuit from one terminal of the condenser I5, over contact I3 bridging contact I3, segment I3", through coil l to line L and back to the other terminal of the condenser I5. Thus the condenser is discharged through the winding l and its stored energy is sufiicient to cause the winding I to attract its armature, thereb opening. contact 1, which deenergizes the winding 5 to disconnect the motor armature 2, and the brakevwinding 4 to stop the motor. If instead of depressing the push button P, the operator had depressed the push button IIJ the action would have been similar, ex-

cept that the condenser I4 would have been charged. Upon the elevator reaching the sec- 0nd floor the segment I3 would connect the contact I3 to the segment I3", the condenser I4 would be connected to the coil I and thus initiate stoppage of the elevator on the second floor.

If, on the other hand, at any time the push button 8 at the third landing is depressed by a would-be passenger on said floor, a circuit is established from line L over contact 8, through condenser 20 to line L and condenser 20 is charged. If subsequently the car reaches the third floor on its upward travel, a discharge circuit is established from one terminal of the condenser 20, to contact li bridging contact II, segment I I over contact 5, through coil 7", to line L and back to the other terminal of condenser 20. Thus the condenser discharges its energy through the coil 1 and the relay is energized and again opens the contact 1, with the result explained heretofore whereupon the elevator stops at that floor to permit the passenger to board the elevator. Thereupon th elevator may be started again by the operator in the car upon movement of the car switch in the desired direction.

Should the passenger on the third floor push the push button 9 for downward travel, the relay I would not function during the upward travel of the elevator as the condenser I9 which is charged upon pressing of the push button 9 can discharge only when the contact 5 is closed, which takes place only'when the switch 6, which controls the downward travel of the elevator is energized. Hence when the elevator moves upward and the push button 9 is depressed the elevator will not stop at that floor until the car is reversed by the operation of the car switch 25 and it travels in a downward direction to permit the charged condenser I9 to energize the coil 1. The elevator is moved in a downward direction by the clockwise rotation of the car switch 25,

which completes a circuit from line L over conconnected to the line L "take the place of the contacts l 'serted from that described heretofore, while the brake winding 4 is energized by closure of contacts 6.

Referring now to Fig. 2 the same shows a modification of the system shown in Fig. l, to

enable the operator to pass a floor even though a push button on said floor has been depressed and which would normally cause the car to stop. This is desirable if the car is filled to capacity which necessitates the discharge of some passengers before others can be taken on. In this modification a car switch 25 like that of Fig. l is provided with additional contacts 25, 25 on opposite sides of the neutral position of the movable switch contact 25 The system is provided with a relay 26, having an energizing-coil 25, one terminal of which is connected to the contacts 25 and 225 while the other terminal is The relay is further provided with normally closed contacts 2t and 26. The contact 26 is interposed in the connection between the relay coil "l and-line L and the contact 26 is interposed in the connection between the relay coil 'i and the line L Thus when the relay coil 26* is energized-said connections of the coils l and l are interrupted.

To pass a iloor for which a push button has been depressed, the operator moves the handle of the car switch 25 to one of its operating posi tions depending upon the direction in which the elevator is to travel. In addition to the iunctions heretofore described in connection with Fig. 1, such operation also energizes the coil 25 so that the discharge circuit of the condensers i i to ill, inclusive, is interrupted and the coil 'l and l cannot be energized by any charged condenser. This prevents opening of the contact l and the car does not stop until the operator moves the handle to the neutral posi tion or until the car reaches the upper or the lower limit in the hatchway. It will of course be understood that upon movement or the car switch from the operating position to theneutral position, the operator can restore the func tion of any condensers that may have been charged so as to operate in the manner heretoiore described.

Referring to Fig. 3 the same shows a modification of the system Fig. 1 to afford slow down of the car prior to stopping. The system shown in ,Fig. 1 is modiiied in the following manner: The relay 1 is replaced by a relay 3i which has an energizing coil inserted in the circuit in place of the coil i of Fig. l. A second energizing coil 3'3 is inserted in the circuit in place or the coil l The relay has a third energizing coil 33 and normally open contacts Ell 31 and ill. The contacts 3'! are interposed between one terminal of the energizing coil fil and the line L. The other terminal of the coil 3i is connected in series with the safety switches ii l to the line L The switches l5 and t are provided with additional normally open auxiliary contacts 5 and 6 respectively, which are connected in parallel circuit with each other and are interposed between the line L and the contacts Si of relay 3?. The circuit containing the contact Si further includes in series a resistor and an energizing coil St oi a relay 3%, coil 38 having a shunt including condenser it. Relay 38 is provided with normally closed contacts 38*, which of Fig. i. Inin the connection between the shunt field winding 3 and the line L is a shunt field re- .ode 42 'sistor 4|, which is adapted to be short circuited by the contacts 3'! of relay 3?.

The system shown in Fig. 3 operates in a manner similar to that in Fig. 1, except as will now be explained. When coil 37 or 31 is energized by the discharge of one of the condensers upon the car reaching a certain floor, the relay 3'! short circuits the resistor M and thus strengthens the shunt iield of the motor whereupon the motor slows down. At the same time the relay energizes its maintaining coil 31 through a cir cuit from line L over contacts it", through the relay coil 31, the safety switches 2d, to line L so that the relay 3? remains energized after the discharge of the condenser. Closure of contacts 31 energizes the relay 38 through a circuit from line L over contacts 5 or 6 31 resistor coil 38*, to line L The response of the coil 38 is retarded by the resistor 39 and condenser it, which functions to prevent full energization of the coil 33 until the condenser it is charged, thus providing for a time delay during which the shunt field is strengthened and the motor has slowed down. Upon the coil 33 becoming sufficiently energized, the relay 38 opens the contacts 38 which interrupts the energizing circuit of the coils 5 or 6 of the respective electromagnetic reversing switch 5 or ii thereby opening the motor armature circuit and stopping the motor in the manner aforedescribed. After the elevator has reached the desired landing and the door is opened, one of the door switches A l opens, thereby interruptin the energizing circuit oi the coil Si which causes opening of the contacts 37 til and 31. Thus the relay 3? is deenergized, the short circuit of the resistor ii is opened, and the relay 33 is deenergized so that upon reoperation of the car switch '25, the elevator can again be started in the desired direction as heretofore described.

Fig. 4 illustrates a further modification oi the system disclosed in Fig. 1, wherein the capacity of the individual condensers associated with the various push buttons may be reduced, without reducing their effectiveness. In this case the condenser upon discharging does not directly energize the stop relay indicated by the numeral '5 in Fig. l, but the relay is energized through a gaseous three electrode thermionic tube, the grid of which is rendered positive so as to initiate a. discharge through the tube and the energizing coil or" the relay connected therewith when the floor selector switches connect the respec tive condenser to the grid upon the elevator arriving at the respective floor.

Fig. 4 shows only that part of the diagram which is a modification from the connections shown in Fig. 1. The condensers It to 2|, of which only two are show in Fig. 4., are connected in the manner described to floor selectors H and I2.

The system includes a gaseous thermionic tube 42, having a cathode 42 an anode 42 and a control electrode or grid 42. The cathode is connected to the positive line L through resistor 43 and to the negative line L through resistor 44. The grid is connected to the negative line L through resistor 45, and it is also connected to one pole of each of the auxiliary contacts 5 and 6 the other side of these contacts being connected to the contact segment li and 12*, respectively, the same as in Fig. l. The relay 1 is provided with a single energizing coil 1 one terminal of which is connected to the an- The second terminal of the winding I is connected to normally open contacts 5 and 6', which are attached to the switches 5 and 6, respectively, and are connected in parallel with each other. The circuit of the coil 1 is completed through the auxiliary contacts 5' or 6 selectively to the line L The system thus modified operates as follows: After a push button has been depressed and the car has been started in the manner described in connection with Fig. 1 and reaches the corresponding landing, a discharging circuit is established from one terminal of the respective condenser, which we assume for the purpose of illustration would be the condenser I1, through contacts I2 l2, and I2 of floor selector switch I2, contacts to the grid 42, while the other terminal of the condenser is connected to line L. The positive potential of the charged condenser I1 is thus impressed upon the grid 42 and the tube 42 becomes conductive, thereby establishing a circuit from line L through contacts 6 energizing coil 1, the tube 42, through a resistor 44 to line L. The relay I is thus energized and opens the contact 1 thereby deenergizing the switch 0 to stop the motor in the manner aforedescribed. The resistor 45 is of a high ohmic value but is selected so that the condenser I1 is discharged immediately after it has made the tube 42 conductive. Upon opening of the contact 6 the circuit through the tube 42 is again,

interrupted while the grid has impressed upon it the negative potential of the line L, thus rendering the tube 42 non-conducting until the floor selector connects another condenser to the grid of the tube to again render it conducting and to repeat the cycle described.

Referring now to Fig. the same is a modi- I fication of the system shown in Fig. 3. The reversing switches 5 and 6 are the same as those shown in Fig. 3. The relay 3'! is provided with additional contacts 31 and 31 while the contact 31 has been omitted. Also relay 38 and resistor 39 and condenser 40 have been omitted. Added to the system is a retiring cam 50 having an energizing coil 50. Th retiring cam is attached to the car and cooperates with hatchway limit switch 5|. A hatchway limit switch is arranged in the hatohway at each floor, but only one is shown in the diagram. The limit switch is provided with normally closed contacts and when more than one switch is employed, their contacts are connected in series. When the retiring cam coil is deenergized and the car approaches the corresponding landing the cam opens the limit switch 5|, 50 is energized the cam is withdrawn, so that upon passing the limit switch 5| is not opened.

The coil 50 is connected in series with the contact 31 and the contacts 5 or 6 to the lines L and L The brake solenoid coil 4 of Fig. 1 is connected in Fig. 5 to L through contacts 5 or 6 and directly to line L.

The operation of the system shown in Fig. 5 is in general similar to that disclosed in connection with Fig. 3 except for the following:

When the car approaches a desired landing one of the coils of the relay 3 1 is energized in the manner aforedescribed, whereupon the contact 31 closes to strengthen the field 3 of the motor by short circuiting the resistor H, which slows down the motor. At the same time the contact 31 is opened thereby deenergizing the retiring cam energizing coil 50 which is connected in series therewith. As the car levels with the landing, the retiring cam opens the contacts or the while when the coil limit switch 5| which is connected in series with the energizing coils 5 and 6* of the reversing switches 5 and 6, thus disconnecting the motor from the line in the manner aforedescribed and setting the brake. Upon deenergization of the relay 3! it also closes the contacts 31 thereby short circuiting the hatchway limit switches so as to permit restarting the car after it has made its stop. Opening of the limit switch 5| also interrupts the maintaining circuit of the energizing coil 31, so that the relay 3! is again deenergized to return the system to condition for restarting and a new cycle of operation.

Referring now to Fig. 6 the same illustrates an installation of two elevators, each controlled by a system similar to that shown in Fig. 1, but arranged so that both..elevators are controlled by the same floor push buttons in the manner, that the first elevator which approaches a iven floor, on which a floor button for a given direction has been pressed, will stop. Only so much of the system has been shown and will be explained as is necessary to a proper understanding after consideration of the operation described in connection with Fig. 1.

The two elevators are provided with car switches and BI, and with car buttons 1| to 14, inclusive, and BI to 84, inclusive, respectively. The common floor buttons are designated by the numerals 9I to 96, inclusive. One car drives the floor selectors 9'! to 99, inclusive, while the other car drives corresponding floor selectors I00 to I02, inclusive. The condensers coordinated to the push buttons II to 14, inclusive, are designated by the general numeral I03, those coordinated with the push buttons 8| to 84, inclusive, by the numeral I04, and those coordinated with the floor buttons 9| to 95, inclusive, by the numeral I05. The motor 62 is controlled by the reversing switches 64 and 6B and by the stop relay 68, while the second motor 63 is controlled by the reversing switches 65 and 6 1 and stop relay 69.

It will be observed that if both elevators are in the lowermost position andthe up floor button -is depressed, the corresponding condenser I05 is charged. If new the operator moves the car switch Si in the upward direction, the motor armature 63 is energized and the second elevator moves upwardly until it reaches the third floor, whereupon the charged condenser I05 is connected by the floor selector I00 across the upper coil 09* of the relay 69, and "the relay opens the energizing circuit of the switch 65, thereby stopping the elevator on that iloor.

If the first elevator is also moving in the upward direction but is lagging behind the second elevator, the condenser I05 is deenerg'ized by the stoppage of the second elevator as aforedescribed, so that the first elevator passes the third floor without being stopped. To accomplish this result it will be noticed that the stationary contacts corresponding to the different floors of the floor selectors El and I00 are connected together and are also connected to the corresponding floor buttons. Similarly the corresponding contacts of floor selectors 98 and IOI are connected to each other and to the corresponding floor buttons, while the contacts of floor selector 09 are connected to the car buttons of the first elevator in the manner described in connection with limit switch I3 of Fig. l, and the contacts of floor selector I02 are connected to the car buttons 8l to 84, inclusive, and to the condensers I04 in a similar manner.

The control of the electromagnetic brakes and of the shunt field windings of the motors is similar to that shown in Fig. 1. Also the various limit switches are connected in a suitable manner to the respective elevators as has been described in connection with Fig. 1. I

It will be observed that the system shown in Fig. 6 may be used in connection with more than two elevators, in which case it is only necessary to supply additional push button switches in the cars of each elevator and additional condensers and limitswitches. The connection of these instrumentalities will be obvious from the figures shown and the foregoing description.

It will also be obvious that the modifications shown in Figs. 2 to 5 may be applied to the system shown in Fig. 6.

Other modifications not shown or described in detail will be obvious. For instance it is possible to use alternating current motors supplied from an alternating current line and supply the energy for charging the condensers from the alternating current source through a rectifier or from some other source of direct current. It is also possible to supply the energizing circuits of the electromagnetic reversing switches from the same direct current source or rectifier.

The drawings and descriptions do not show all of the customary safety interlocks, retiring cam limit switches, and other safety devices which are standard equipment with passenger elevators. Their use and the connection in the system will be obvious to one skilled in the art.

Furthermore, the system may be applied to multi-speed elevators driven either by direct or alternating current and the customary floor indicators and other signaling systems may be combined with the present system in the conventional manner.

What I claim as new and desire to secure by Letters Patent is:

1. In control for an electric motor driven traveling device, in combination, stopping means for the traveling device including electroresponsive means requiring energization for stopping. energy storing means to the discharge of which said electroresponsive means is responsive, and controlling means affording charging of said energy storing means at will and providing for discharge thereof dependently upon entry of the traveling device into a given zone of travel.

2. In control for an electric motor driven travelin device, in combination, stopping means for the traveling device including electroresponsive means requiring energization for stopping, energy storing means to the discharge of which said electroresponsive means is responsive, and controlling means for said energy storing means providing for charging thereof at will and for a discharge of the same dependently upon entry of the traveling device into a given zone of travel and also dependently upon or independently of direction of travel of the traveling device when entering such zone, according to prior optional manipulations of said controlling means incident to charging of said energy storing means.

3. In control for an electric motor driven traveling device, in combination, stopping means for the traveling device including electroresponslve means requiring energization for stopping,

separate energy storing means either of which through discharge effects energization of said electroresponsive means, and controlling means for said separate energy storing means including for efiecting charge thereof individual control switches operable at will, and further including means for effecting discharge of said separate energy storing means dependently upon entry of the traveling device into a given zone and selectively according to direction of travel into such zone.

l. In control for an electric motor driven traveling device, in combination, stopping means for stopping the traveling device including electroresponsive means requiring energization for stopping, a plurality of energy storing means, any one of which through discharge effects energization of said electroresponsive means, individual manual control switches for said energy storing means for effecting charge thereof, and means for effecting discharge of a plurality of said energy storing means progressively upon entry of the traveling device progressively into different given zones of travel.

5. In a control for an electric motor driven travelin device, in combination, starting means for the traveling device, including manual means for effecting starting, means for stopping the device including electroresponsive means requiring energization for stopping, a plurality of energy storing means, any one of which through discharge effects energization of said electroresponsive means, individual manual control switches for said energy storing means operable selectivel for effecting charge of their respec tive energy storing means, and means for effecting discharge of a plurality of said energy storing means singly and selectively upon entry of the traveling device into different given zones of travel.

6. In control for an electric motor driven traveling device, in combination, reversing starting means for the traveling device, including manual means for effecting starting and selection of direction of travel, stopping means for stopping the device including electroresponsive means requiring energization for stopping, a plurality of energy storing means, any one of which through discharge effects energization of said electroresponsive means, individual manual control switches for said energy storing means operable selectively for efiecting charge of the respective energy storing means, and means for effecting discharge of said energy storing means singly and selectively and rendering discharge of each of said energy storing means dependent upon entry of the traveling device into a given zone and also dependent upon direction of approach to such zone.

'7. In control for a. plurality of electric motor driven traveling devices, in combination, stopping means for stopping the devices selectively, said stopping means including a plurality of electroresponsive rneans individual to the traveling devices and requiring energization for stopping their respective devices, a plurality of energy 'storing means, any one of which through discharge afiords, energization of either of said electroresponsive means, individual manual control switches for said energy storing means operable .for effecting charge of their respective energy storing means, and means for efiecting discharge of certain of said energy storing means selectively upon entry into a given zone according to the direction of travel into such zone of the leading traveling device and for directing the discharge to said electroresponsive means which is individual to such leading device.

8. In control for an electric motor driven traveling device, in combination, electromagnetic control means for the traveling device, including starting means and slow down means for slowing down the device in any one of a plurality of given zones along its path of travel, said slow down means including electroresponsive means requiring energization for slowing down, a plurality of energy storing means, any one of which through discharge effects energization of said electroresponsive means, individual manual control switches for said energy storing means for ef- Iecting charge of their respective energy storing means, means for effecting discharge of said energy storing means singly and selectively to said slow down means, and means responsive automatically following energization of said slow down means for effecting, deenergization of said electromagnetic starting means to stop the traveling device.

9. In control for an electric motor driven traveling device, in combination, a reversible motor to effect movement of the traveling device into a plurality of zones of travel, electromagnetic control means for said motor aifording starting thereof in reverse direction and also stopping, manual means through the medium of which said electromagnetic control means is controllable and including a plurality of push button switches, a, plurality of condensers, means effective upon operation of any one or more or said push button switches to store up electrical energy in one or more of said condensers corresponding to the push button switch or switches operated and a zone type selector driven by said motor which affords discharge connections from said condensers selectively to said electromagnetic control means for response of the latter to condenser discharge to effect stopping of said motor.

10. In control for a plurality of electric motor driven traveling devices, in combination, a reversible motor for each device to eifect movement of the respective traveling device into a plurality of zones of travel common to all of the devices, individual electromagnetic control means for said motors, individual manual means controlling the respective electromagnetic control means to effect starting, of said motors selectively in either direction, a plurality of push button switches, a plurality of condensers. means effective upon operation of any one or more of said push button switches to store up electrical energy in one or more of said condensers corresponding to the push button switch or switches operated, and an individual zone type selector driven by each of said motorasaid zone selectors aifording discharge connections from said condenser selectively for response of said electromagnetic control means selectivel 'in favor of the leading traveling device to effect stopping thereof if the selected condenser is charged.

11, In control for an electric motor driven traveling device, in combination, a reversible motor, electromagnetic reversing means for said motor, manual means operable to control said electromagnetic means to start said motor in either direction and to stop the same, including a plurality of push button condensers, means effective upon operation of any one or more of said push button switches to store up electrical energy in one or more of said condensers corresponding to the push button switch or switches operated, a selector coupled to said motor to effect discharge of the energy stored in said condensers for energizing means included in said. electromagnetic means, thereby to effect dc"- switches, a plurality'of .said selector so rendering the enereization of said motor through said electromagnetic means, said selector so rendering the charged condenser effective selectively according to the position and direction of travel of the traveling device.

12. In control for an electric motor driven traveling device, in combination, a motor, electromagnetic circuit making means for said motor, manual means operable to control said electromagnetic means to start said motor and to stop the same including a lurality of push button switches, a plurality of condensers, means effective upon operation of any one or more of said push button switches to store up electrical energy in one or more of said condensers corresponding to the push button switch or switches operated, and a selector coupled to said motor to effect discharge of the energy stored in the condensers for energizing means included in said electromagnetic means, thereby to effect deenergization of said motor through said electromagnetic circuit mak ing means, said selector so rendering the charged condenser effective selectively according to the position of the traveling device and affording stoppage of the traveling device in the selected positions in their natural order independent of the order of actuation of said push button switches.

13. In control for an electric motor driven traveling device, in combination, a reversible motor, electromagnetic reversing means for said motor, manual means to control said electromagnetic reversing means to start said motor in either direction and to stop the same including a plurality of push button switches, a plurality of condensers, means eifective upon operation of one or more of said push button switches to store up electrical energy in one or more of said condensers according to the push button switch or switches operated, and a selector coupled to said motor and arranged to effect discharge of the energy stored in the condensers for energization of means included in said electromagnetic means, thereby to effect; deenergization of said motor through said electromagnetic reversing means, charged condensers eifective selectively according to the position and direction of travel of the traveling device and affording stoppage of the traveling device at the selected positions in their natural order independent of the order of actuation of said push button switches.

14. In control for an electric motor driven traveling device, in combination, electromagnetic control means for the traveling device, manual means for effecting energization of said control means to start the device, stopping means for stopping the device at any one of a plurality of given zones along its path of travel selectively and including electroresponsive means requiring energization for stopping, an electron tube in circuit with said electroresponsive means and having a control electrode, a plurality of energy storing means, any one of which when charged affords potential control of said control electrode to render said tube. conducting and energize said electrorcsponsive means, individual manual control switches for said energy storing means operable selectively :for effecting charge of their re spective energy storing means, and means for subjecting said control electrode to control by the charged condensers progressively upon entry of the traveling device into corresponding zones of travel, at the same time discharging each condenser so selected. a

15. In control for an electric motor driven traveling device, in combination, a reversible motor to effect movement of the traveling device into a plurality of zones of travel, electromagnetic control means for said motor affording starting thereof in reverse directions and comprising an electromagnetic relay energizable to cause said control means to effect stopping, manual means through the medium of which said electromagnetic control means are controllable,

including a plurality of push button switches, a

plurality of condensers, means effective. upon operation of any one or more of said pushbutton switches to store up electrical energy in one or more of said condensers corresponding to the pushbutton switch or switches operated and a zone selector driven by said motor which affords discharge connections from said condensers selectively to said electromagnetic relay for energization thereof by condenser discharge to effect stopping of said motor.

EDWIN W. SEEGER. 

